1. Field of the Invention
This invention relates to synthetic fibers having excellent antistatic properties.
2. Description of the Prior Art
It is known that one defect of synthetic fiber products such as products of polyester or polyamide fibers is their propensity to build up static charges which lead to electrostatic generated problems such as the occurrence of crackling sounds, clinging to the human body and the adhesion of dust to the fibers. Surface-treating of fibers with an antistatic agent and inclusion of an antistatic agent in fibers are two general methods of controlling these electrostatic caused problems. The former method has the defect that the antistatic agent drops off upon laundering, rubbing, etc. and the antistatic effect is reduced. In contrast, the latter method is superior in that the antistatic effect is long lasting.
It is well known that polyalkylene oxide-type compounds are effective as antistatic agents. In particular, incorporating a block copolymer containing a polyalkylene oxide component is considered to be most suitable for obtaining fibers having a permanent antistatic effect. When, however, this block copolymer is introduced into fibers by an ordinary blending method, the polyalkylene oxide component tends to be confined within the molecules of the fibers with reduced mobility, and, therefore, cannot readily produce an antistatic effect.
In an attempt to circumvent this problem, U.S. Pat. No. 4,034,441, for example, proposes fibers in which a block copolymer containing a polyalkylene oxide component is dispersed as fine striae along the fiber axis. With these fibers, however, the reduction of the mobility of the polyalkylene oxide component cannot be prevented sufficiently, and electrostatic-induced problems tend to occur in an atmosphere having a low humidity.